JPS58502089A - Catalytic desulfurization method for acidic gas containing H↓2S - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Catalytic desulfurization of acidic gases including H2S The present invention uses H2S and optionally a total amount of at most 6 volumes of C82 and ( or) Catalytic desulfurization of acid gases containing COS and sulfur or in some cases relates to a method for recovering this sulfur compound in the form of S02.

Acid gases containing 828 at concentrations of at most 15 parts by volume are obtained in various industrial processes. Ru. The H2S content of such gas is too low to be used in the burner as a first step. It is impossible to process it in typical sulfur equipment, which involves combustion of acid gases. . In fact, this combustion occurs when the H2S' content exceeds 15 volumetric acid gases. It is technically possible. H2 contained in acidic gas containing 15 volumes of H2S Various catalysts are used in the presence of oxygen or air to recover S in the form of sulfur. It was proposed to oxidize catalytically.

Therefore, British Patent No. 6,22,324 states that A mixture of this acidic gas and an appropriate amount of oxygen or air is heated at 100-400% Oxides of titanium, especially orthotitanium activated by heating, at temperatures of °C A method is described for oxidizing sulfur by contacting it with a catalyst made of an acid. It is being

Although interesting, this method has some drawbacks. all to make up the catalyst It is particularly necessary to use orthotitanic acid without soluble salts. this pure life Requires cumbersome catalyst neutralization and washing steps (several sequential steps) to obtain the product. Ru. Moreover, catalysts containing only orthotitanic acid are insufficient for industrial implementation. It has selectivity. To improve this selectivity, the catalyst can be pre-sulfurized. It is necessary to This constitutes an additional step that increases processing costs.

The results of the above methods particularly include oxides of titanium as well as sulfates of alkaline earth metals. It has been found that improvements can be made by using catalysts. Such catalysts are exhibits long-lasting properties and increased activity. This makes it possible to carry out the oxidation reaction of H2S. This results in sustained high sulfur conversion and excellent selectivity.

H2S and possibly a total of no more than 3 volumes of C32 and/or Catalytic desulfurization of acidic gases containing CO8 and sulfur, and in some cases SO The method of the invention for the recovery of this sulfur compound in the form of a controlled amount of gas containing free oxygen, preferably in the form of a mixture, of 100-6 of the type that is brought into contact with a catalyst based on titanium oxides at a temperature of 00°C. It is. In addition to titanium oxide, the catalyst contains calcium, strontium, barium, It is characterized by containing sulfates of alkaline earth metals selected from magnesium and magnesium. Ru.

A method of the invention comprising an oxide of titanium and a sulfate of an alkaline earth metal as described above. Catalysts containing titanium oxide and calcium sulfate among the catalysts that can be used in Or preferable. This catalyst exhibits excellent mechanical resistance.

A catalyst containing titanium oxide and a predetermined alkaline earth metal sulfate is Additionally, 30% by weight of silica, alumina, clay, silicates, titanium sulfate, and cera It can contain components selected from among Mic fibers.

Made essentially of titanium oxide and alkaline earth metal sulfates, or even in excess In the catalysts used in the present invention containing additional components of the type described above, titanium oxide is The weight ratio of the calcined catalyst expressed in TlO2 to the total weight is about 60-99, preferably More preferably, it is 80-99%. On the other hand, sulfate of alkaline earth metal also The weight ratio to the total weight of the catalyst is preferably about 40-1%, preferably 20-1%. .

These catalysts are closely packed with nine oxides, alkaline earth metal sulfates, and incidental other components. Whether the product is mixed with titanium oxide or other incidental impregnated with alkaline earth metal sulfate. natural ingredients and products from any suitable source from which they can be obtained. It can also be made by other methods.

The production of catalysts is for example formed on the basis of titanium oxide and optional additional components. compounds that in turn produce sulfate anions in Ni or sulfur hydroxylamine and then alkaline earth metal cations Compounds, especially acetates, nitrates, or chlorides of alkaline earth metals, can be mixed with titanium oxide. Impregnate the material to form an alkaline earth metal sulfate into the gap between the objects to be used as a base. Drying and calcining the product at 300-900°C, preferably 350-800°C This is done by Formed on the basis of titanium oxide and other fortuitous components In particular, the object described in French Patent Application No. 8009126 of April 26, 1980 2481145), oxidation of amorphous and/or defective crystals. Using titanium or, for example, ortho- and meta-titanic acids, and oxyhydroxy acids Any material that can be converted to titanium oxide by force calcining, such as titanium oxide, can be used. It can be obtained by

The impregnation of the formed material is such that the weight ratio of SO4 to TiO2 is approximately 0.01-0.15. , preferably 0.05-0.10. The weight ratio of alkaline earth metal to TlO2 is approximately 0 ．． 004-020, preferably 002-015.

In the method of the invention, titanium oxide, other incidental components, and alkali sulfate are Mixtures containing earth metals or compounds containing sulfate anions and alkaline earth metals Starting from a mixture of compounds containing cations, French Patent Application No. 8009126 This starting mixture is kneaded, shaped, dried and force-calcined steps similar to those of the method of The catalyst can be recovered by a treatment including is a reaction that produces titanium oxide and sulfate anions and alkaline earth metal cations, respectively. The properties of the compound and the weight ratio of SO4 and TiO2 on the one hand, and the alkaline earth on the other hand. The weight ratio of metal to TiO2 is determined by the impregnation of an object formed on the basis of titanium oxide. This corresponds to that in the preparation of the above catalyst by One variation of this method In terms of form, ilmenite is obtained by hydrolysis, filtration, and drying followed by sulfuric acid treatment. such as sulfuric acid, titanyl sulfate, titanium sulfate and/or salts of titanium Titanium oxide containing sulfate anions in the form of basic salts, and containing only this titanium oxide. starting materials, other fortuitous components, and compounds that yield alkaline earth metal cations. Use a mixture. Weight ratio of so4 to TlO2 and alkaline earth metal to TiO2 The weight ratio is as above.

This titanium oxide obtained by treating ilmenite with sulfuric acid is the same (the titanium oxide mentioned above). It can be used in the preparation of catalysts by impregnation into tunic-based objects. Ru.

In this case, this titanium oxide-containing substance produces especially alkaline earth metal cations. Impregnated only by compounds.

The weight ratio of S04 to TlO2 on the one hand and the alkaline earth metal to 7102 on the other hand Processing is performed for those whose weight ratio with the above value is as follows.

In other methods of making catalysts using the present invention, titanium oxide and other incidental components is formed on the basis of sulfiding substances containing alkaline earth metal cations. this The sulfurization is preferably carried out in a mixture of SO2 and air at a temperature of 250-550°C. It is carried out using a gas containing Weight ratio of S○4゛TlO2 and alkaline earth metal The weight ratio of genus: TlO2 is as above. Sulfurized products may dried and then heated to a temperature of 300-900°C, preferably 350-800°C. Set aside and roast.

The catalyst used in the present invention has a s-30[ 1m2ﾃ＼Preferably 10-241]m2/? specific surface area and measured by mercury infiltration method. and 0.05-0.6 cm5/l, preferably 0.1-0.4 cm3/f It has a total pore volume. Its wear resistance is less than 2 inches.

Abrasion resistance was measured using a No. 24 sieve with a diameter of 20 cm from the AFNORX 11-501 series. Loaded with 100 grams of catalyst fine particles, it was placed on a vibrator with the trademark 1” ENwICK REX. Therefore, it represents the powder indicated by Durham obtained by shaking for 10 minutes. vinegar. Wear resistance is expressed in chi.

The acid gas treated in the method of the invention, namely H2S, and optionally at most 6 The total concentration of C82 and/or COS in weight percent is within broad limits. The concentration of H2S can be changed. The present invention has a concentration of at most 15 volume factors. A total amount of H2S and possibly at most 6 parts by volume, preferably at most 1 part by volume Acid gas containing C82 and/or CO8, especially 0.01-12 volumetric of H2S and possibly at most one volume of total amount of C82 and/or C It is advantageous to use it in the treatment of acidic gases containing O8.

The acid gases treated with the present invention can have various origins. especially such acids Gases include natural gas, gas obtained by gasification of carbon or heavy oil, or ion gases. A gas obtained by hydrogenating sulfur compounds from a corrugated factory may be used.

Oxidation of H2S and release of acid gases used for the conversion of the compound cs2 and incidental COS Although pure oxygen can be used as the oxygen-containing gas, air, oxygen-rich gas, etc. air or a mixture of oxygen and inert gases other than nitrogen in various proportions .

The acidic gas and the free oxygen-containing gas can be contacted with the catalyst separately. death However, in order to obtain a very homogeneous gaseous reaction medium, the acid gas and the free Preferably, the mixture is mixed with a gas containing oxygen and the resulting mixture is brought into contact with a catalyst.

The contact time between the gaseous reaction medium and the catalyst in each desulfurization zone used was o, 5- It may be io seconds, especially 1-6 seconds. These values were determined at standard pressure and altitude. It is.

As mentioned above, the catalytic desulfurization in the present invention is carried out at 100-600°C, preferably at 1 Temperatures of 80-500°C can be used.

The possible H2S content of at most 5 volume factors (free H2S content + compound cs 2 and the theoretically obtainable H2S content from the COS that may be present) In one embodiment of the method of the present invention used for desulfurization of acidic gas having and a gas containing free oxygen, preferably in an oxygen:possible H2S molar ratio of 0. titanium oxide in the form of a pre-prepared mixture in an amount having a value of 35-1.8. containing the above types of alkaline earth metal sulfates, and only one at a temperature of 180-500℃ A gas containing free oxygen and an acidic gas are brought into contact with the catalyst placed in the reaction zone for 1-6 seconds. are catalyzed so that the molar ratio R of oxygen and possible H2S is 0.35-0.6. When the temperature of these gases introduced into the medium region is 180-350℃, the possible H2 70-98% of S is converted to sulfur and SO2, and the selectivity for sulfur is over 90%. It is above. 0.35-0.5, especially a value of H of about 04 and a catalyst area of 200-250°C. The selectivity for sulfur is greater than 98% relative to the temperature of the gas in the region.

When the ratio R reaches a value of 1.8, the sulfide compounds present in the acid gas are completely converted to S 02.

For the value of the ratio R of 0.6-1.8, the possible H2S contained in the acid gas is It is recovered in the form of a mixture of H2S and SO2, and the conversion rate of H2S is over 90 coefficients. Therefore, when the ratio R takes a value of 1-1.8, the selectivity of SO2 ranges from 40 to 100. increase

If necessary, remove any sulfur from the catalytic reaction area after separating any sulfur it may contain. The effluent can be subjected to supplementary purification treatment.

Method of the present invention used for desulfurization of acidic gases with a possible H2S content of about 5 bodies or more Other embodiments of the invention are optionally separated by one or more intermediate catalytic regions. each titanium oxide and the above type, including a first catalytic region and a last catalytic region. passing the acid gas through a plurality of catalyst zones in series containing an alkaline earth metal sulfate; and, - In each said area, free oxygen-containing scum, preferably in a mixture with an acidic gas, is The proportion of oxygen entering each of the first and middle catalytic regions is 3-5 volumes of acid gas. About 0.7-1.2 of the possible H2S theoretically required to convert to sulfur and preferably about [1,8-1 times, - The temperature of the gas entering each catalyst zone is 180-350°C, preferably 200-25°C. - adjusting the contact time of the reaction gas and catalyst in each region to 1-6 keeping it within seconds; - Treat the scum from each initial and intermediate catalytic region and remove it by condensation. The sulfur contained in the waste is separated and the sulfur-free waste is sent to the inlet of the next area. Adjust the feed to a value of 0.35-1.8 and treat emissions in this area if necessary. and separating by condensation any sulfur it may contain; However, the number of intermediate catalytic regions is such that at most the acid gas is It is something that contains H2S that can be purified by 5 bodies, It consists of

If necessary, collect the effluent from the last catalytic region, which it may contain. After separation of the sulfur, a supplementary purification process is carried out. This treatment remains in the effluent Depends on the nature of the gaseous sulfide compound.

Regarding the value of the ratio H of oxygen to possible H2S at the entrance of the last catalytic zone: The effluent from this area, after separating out any sulfur it may contain, is H2S (R is 0.35-11.5) or 5o2 (R is 1.7) as a sulfide compound -1.8) or various ratios (intermediate values of R) of H2S and SO2. Wear.

In the first and middle catalytic regions, the selectivity for oxidation of H2S to sulfur is over 90% , the ratio of oxygen (R is 0.35-0.5) and the temperature of the gas at the inlet of each of the above regions. In the preferred conditions mentioned above for the degree, it even exceeds 98%.

In each of the two above-mentioned special forms of implementation of the method of the invention, optionally The purification ancillary treatment used may be present in the effluent from the single or last catalytic zone. depends on the nature of the gaseous sulfide compounds present.

When the effluent contains only H2S as a gaseous sulfur compound, the gas is cleaning with a solution of amine, such as methyljetanolamine, or This effluent can be incinerated if the H2S content of the effluent is not too high. Ru. Effluents containing a recoverable content of S02 as the only gaseous sulfur compound For this purpose, adsorption on alkaline alumina or manganese oxide can be used. Wear. When the effluent contains H2S and 802 at the same time, the ratio H Adjust the molar ratio of H2S:SO2 to a value of approximately 2:1 and Standard catalyst CL such as alumina or titanium oxide at temperatures of 0-160°C Regeneration in which sulfur production reaction occurs between H2S and 802 by contact with AUS method or if the total content of H2'S and SO2 in the effluent is very low. Mushroom effluent can be removed by direct ashing.

The effluent of the last catalyst zone has a molar ratio of Has:SO2 or H2S and S of about 2:1. Standard catalyst CL based on alumina at a temperature of 80-160 °C with O2 Regeneration in which sulfur production reaction occurs between H2S and S02 by contacting with AUS Possible H2S content beyond about 5-body purification is subjected to a supplementary purification process consisting of In the case of desulfurization of acidic gases with a large amount of oxygen, oxygen may used in the last catalyst oxidation zone to avoid sulfidation of this catalyst by contact with US. At least a minimum of one-eighth, advantageously half, preferably all of the catalyst contained in the Made of a substrate containing a large portion of aluminum, preferably made entirely of alumina. a catalyst which has been prepared, on which at least Fe, C○, Ni, Cu, and Z are added. A compound of a metal selected from n, in particular iron sulfate, is precipitated and said substrate has a 01] m2/ii', preferably having a specific area of 50-120 m2/r Advantageously, the catalyst comprises 5-10%, preferably 5-10%, by weight of the calcined catalyst. preferably contains an amount of metal compound corresponding to the total amount of metals in groups 2-6.

According to this example, the acid gas with a possible H2S content of more than 5 vol. The method of the invention may be separated by one or more intermediate catalytic regions, as the case may be. said first and intermediate catalyst regions; Each region contains titanium oxide and a predetermined type of alkaline earth metal sulfate. passing said acid gas through a plurality of catalyst zones in series, including: At least a minimum of one-eighth, advantageously half, preferably all of the catalyst used in the region , preferably made of a substrate containing a large proportion by weight of alumina. It is a catalyst made of only Fe, Co, Ni, and Cu. , and compounds of metals selected from Zn, especially iron sulfate, are precipitated to form V. The body has a specific area of 30-300 m2A, preferably 50-120 m2/l. Advantageously, the catalyst has a concentration of 0.5-10%, preferably 0.5-10% by weight of the calcined catalyst. Preferably, it contains an amount of metal compound corresponding to 2-6% of the total amount of metal, - in each said catalyst zone a gas containing free oxygen, preferably in a mixture with an acidic gas; , the ratio of oxygen entering each of the first and middle catalytic regions is 5-5 volumes of acid gas. About 0.7-i of the possible H2S theoretically required to convert to sulfur, 2 times, preferably about 0.8'-1 times; - The temperature of the gas entering each catalyst zone is 180-350°C, preferably 200-25°C. - regulating the gaseous effluents from each initial and intermediate catalytic region to 0°C; Treat a substance to separate the sulfur it contains by condensation, and the sulfur is removed. directing the effluent to the entrance of the next area; H2S by adjusting the molar ratio of 02:H2S at the entrance of the last catalyst zone : To obtain an effluent containing H2S and SO2 with a molar ratio of SO2 of about 2:1. , The gaseous effluent of the last catalyst zone, after separating the sulfur it contains, is 80-1 Contacted with the standard catalyst CLAUS based on alumina at a temperature of 60 °C. In addition, a sulfur production reaction is caused between H2S and S02 to perform a regeneration purification method. However, the catalyst is heated to a temperature of 200-400°C when sulfur is attached to it. regenerated by purification with free oxygen-free gas at be done.

The present invention will be illustrated by examples, but these are not intended to limit the invention.

Example 1 For catalytic desulfurization of acidic gas with the following composition in the cross product ξ-set, 1.1 The reaction was carried out in a fixed bed catalytic reactor containing m3 of catalyst. This reactor is on the one hand is equipped with a gas conduit with a small hole for introducing gas containing free oxygen. Yes, it has a direct heat exchanger between the small hole and the reactor inlet that acts as a reheater. On the other hand, it is equipped with a gas exhaust pipe extending the outlet of the reactor, which is equipped with a A sulfur condenser is provided to remove the sulfur. The gas passing through the inlet passes through the catalyst as it exits the reactor. crossed the floor.

The catalyst used is a product made of titanium oxide and calcium sulfate with the following properties: It was made up of things.

Ti○20 weight content・・・・・・・・・・・・・・・898%CaSO Weight content of 4・・・・・・・・・・・・10.2% Specific surface area・・・・・・ ・・・・・・・・・・・・・・・・・・・・・146　m2/9 Total pore volume・ ・・・・・・・・・・・・・・・・・・・・・・・・ 0.35 C713/9 wear resistance Wearability・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ ...04% This catalyst was prepared as follows.

Weight ratio SO4:　Sulfuric acid ilmine containing sulfate anions in an amount such that TiO2 is 008 Titanium oxide suspension obtained after hydrolysis and filtration using Knight's standard processing method. Calcium nitrate was mixed in so that all the sulfates reacted. Ca: TlO2 At this time, the weight ratio was 00 rolls. The suspension was then dried at 150 °C for 1 h. Ta.

The resulting powder was mixed in the presence of water for 2 hours in a ratio corresponding to 64 parts of powder and 36 parts of water by weight. I practiced for a while. The resulting mixture was then extruded through a 4 mm diameter die to form an extrudate. was dried at 110°C for 4 hours and then calcined at 400°C for 2 hours.

The catalytic desulfurization of the above acidic gas was carried out as follows.

Acidic gas introduced in a conduit at a flow rate of 1.000 Nm3/h at a temperature of 40°C receives air at a flow rate of 40 Nm3/h at ambient temperature (room temperature) through a small hole. I took it. A mixture of acidic gas and air with a molar ratio of 02°H2S of 04 is heated at 200°C. The temperature of the reactor is guided by the passage in the reheater and then the temperature of the reactor is was injected into. The contact time between the mixture and the catalyst in the reactor was 4 seconds. . This corresponds to VVH of 9001-1-1. Gas exits the reactor via a drain pipe. The smoky effluent no longer contained free oxygen and the temperature was 27 °C. child The effluent was cooled to 170"C in a condenser and the sulfur contained was separated. Condensation The gas exiting the vessel contains 0.4 volume purified concentration of H2S as the only sulfur compound. Ta.

Similarly, the conversion rate of H2S was 805%, and the selectivity of sulfur was 1-100%. .

As a comparison, calci prepared like Queen's but under similar conditions. This test was repeated using a catalyst based on titanium oxide without umium.

That is, adding calcium salt to the titanium oxide suspension was omitted.

The conversion rate of H2S was only 35 parts, and the selectivity of sulfur was 95 parts.

Example 2 Three reactors in series for catalytic desulfurization of acidic gases with the following components at volume 2 cents: It consists of a first reactor, a middle reactor, and a last reactor, each with a The experiment was carried out in a facility containing 11 m3 of the catalyst used in Example 1. These reactors are carried out similar to that specified in Example 1, and therefore each containing free oxygen on the other hand. a gas conduit and a reactor inlet with a sump hole for injecting a gas containing the gas, and the like. On the other hand, a gas extending the outlet of the reactor is equipped with a condenser for sulfur to cool the vapor. Contains drain pipes. Condenser for sulfur associated with each first and intermediate reactor The gas outlet is provided in the next reactor upstream of the small hole provided in the relevant conduit. connected to a gas conduit.

The catalytic desulfurization of acidic gas defined at the beginning of this example is carried out as follows.

1.000 Nm' at a temperature of 40"C by the first reactor gas conduit The acid gas introduced at a flow rate of 75 N at ambient temperature through the small hole in the tube mentioned above It receives injected air at a flow rate of m5/h. This amount of air is the filtration volume of acid gas. This corresponds to the theoretical amount needed to oxidize sulfur in H2S. Molar ratio 02: A mixture of acid gas and air with H2S of 017 will last at a temperature of 200°C. is conducted through a heater associated with the reactor, and then at this temperature the reaction injected into the vessel. The contact time between the mixture and the catalyst contained in the first reactor was 4 seconds. Met. This corresponds to a VVH of 900 h-T. First reaction through the drainage pipe The gaseous effluent leaving the vessel no longer contains free oxygen and has a temperature of 333°C. It was. This effluent was cooled to 175°C in a condenser associated with the first reactor; The sulfur it contained was separated. The temperature is 175℃ and the H2S content is 56 Volumetric purification, the gas leaving the condenser is fed into the gas line of the intermediate reactor at ambient temperature. The small holes provided added 75 Nm'/h of additional air. this new The amount of air is required to oxidize the sulfur of H2S, which is equivalent to the six-body purification of the gas. corresponds to the theoretical amount required. Molar ratio 02: H2S is the obtained gas of O'27 The mixture was cooled in this reactor before being injected into the intermediate reactor at a temperature of 200°C. It was heated to this temperature by passing through a reheater.

The contact time of this mixture with the catalyst in the intermediate reactor was likewise 4 seconds (at 900 h-1). equal VVH). The gaseous emissions leaving the intermediate reactor through the drain are also It no longer contains free oxygen, the temperature is 335 °C, and the H2S content is 2.40 volume purified. there were.

This effluent is cooled to 175°C in a condenser belonging to the intermediate reactor to The owl was separated. The gas coming out of this condenser has a small hole in the gas conduit of the last reactor. At ambient temperature, the additional air is a gaseous mixture with a molar ratio of 02:H2S. It was added to make it 0.4. This gaseous mixture is passed through the reheater of the last reactor. the reactor at this temperature. was injected into. The contact time of the mixture with the catalyst in the last reactor was 4 seconds. (VVH is 900h-1). The gaseous effluent coming out of the last reactor is no longer There was no free oxygen and the temperature was 295°C. This effluent is the final reactor condensate. It was cooled to 175°C in a condenser to separate the sulfur it contained. said condenser outlet gas containing H2S at a concentration of only 046 volume as the only sulfide compound in was obtained.

The total conversion of H2S was 94%. This converted H2S is completely in the form of sulfur. (sulfur selectivity is 100%).

Example 3 Catalytic desulfurization of acidic gas with the following volumetric composition was carried out.

cs2・・・・・・・・・・・・・・・015chiH20・・・・・・・・・・・・ ... Treated with equipment similar to that described in Section 7 Example 1 and containing the same volume of catalyst. Ta.

The catalyst used was made of titanium oxide and barium sulfate and had the following properties.

Weight content of TlO2・・・・・・・・・84% Weight content of BaSO4 ・・・・・・・・・・・・16 coefficient area・・・・・・・・・・・・・・・・・・ ・・・・・・107　m279Total pore volume・・・・・・・・・・・・・・・・・・ ・0.32　m571 wear resistance rate・・・・・・・・・・・・・・・・・・・・・ ...02% This catalyst was prepared by the operation defined below.

TiO2 obtained after hydrolysis and filtration by standard treatment of ilmenite sulfate. The tan suspension was dried at 180° C. for 1 hour. Weight ratio 304: TiO2 was 008.

The powder obtained is expressed in weight ξ-cents in the presence of water and barium nitrate. Knead using titanium oxide powder of Part 64, barium nitrate of Part 8, and water of Part 28. It was.

The weight ratio Ba:TiO2 was then 0113. Pour the resulting mixture into 5 cylinders in diameter. extruded through a die, dried the extruded product at 110°C for 4 hours, and Then, it was calcined at 500°C for 1 hour.

The catalytic desulfurization of acidic gas defined in this example was performed as follows.

The introduced acidic gas is heated to 5 D at ambient temperature through a small hole provided in the conduit. Receives injected air at a flow rate of Nm'/h. Molar ratio 02: (possible) H2 A mixture of acidic gas with S of 0.5 and air is heated to 200℃ by passing it through a reheater. temperature and then introduced into the reactor at this temperature. The mixture and reactor The contact time with the catalyst contained in was 4 seconds (VVH is 900 h-'i-) . The gaseous effluent leaving the reactor via the gas vent no longer contains free oxygen. First, the temperature was 298°C. This effluent is cooled to 170°C in a condenser. The sulfur it contains was separated. The gas coming out of the condenser has a volume of 0.21 cm. It contained only possible H2S.

The possible H2S conversion was 89% and the sulfur selectivity was 99%.

For comparison, under similar conditions, titanium oxide powder and water as above were mixed. When kneading/(barium-free, titanium oxide prepared without adding lithium salts) This test was repeated using a catalyst based on chlorine.

The possible H2S conversion was only 28% and the sulfur selectivity was 94%.

Example 4 Catalytic desulfurization of an acid gas with the same composition as that of the acid gas in Example 1 for conversion of H2S This was done by creating only so2.

The equipment and catalyst were the same as in Example 1.

Desulfurization was performed as follows.

Acid introduced by a conduit at a flow rate of 10 D Nm'/h at 40 °C The gas is supplied through a small hole in the conduit at a flow rate of 170 Nm3/h at ambient temperature. mixed with air injected in quantity. Acidic gas with a molar ratio of 02:H2S of 17 and air The mixture was brought to 200°C through a reheater and then introduced into the reactor at this temperature. Ta. The contact time between the mixture and the catalyst was 4 seconds (VVH = 900 h-+ ). A gaseous effluent exited the reactor at a temperature of 484°C. Condense this effluent It was cooled to 170°C in a container.

The gas coming out of the condenser is the only sulfur compound, so the conversion rate of H2S is 100%. The selectivity of so2 was 100%.

For comparison, the comparative catalyst used in the comparative test of Example 1 was used under similar conditions. The lever test was repeated.

Under these conditions only 79 units of H2S were converted. The selection rate of S02 is 100chi. Ta.

Example 5 Catalytic desulfurization of acidic gas with the following volumetric composition was carried out.

The process consists of three catalytic oxidation reactors in series: an initial reactor, an intermediate reactor, and and the last reactor. The series reactor has two parallel reactors. A supplementary purification system including a medium converter was connected.

The catalytic reactor was similar to that used in Example 1, so each Inlet and outlet separated by catalyst bed and small hole for injecting gas containing free oxygen and a reheater between this small hole and the reactor inlet, connected to the reactor inlet. The reactor outlet is extended with a gas conduit and a sulfur condenser to cool the vapor. and a gas exhaust pipe. Condensation for sulfur belonging to each initial and intermediate catalytic reactor The gas outlet of the reactor is connected to the gas conduit installed in the next catalytic reactor in the series. Connected upstream of the hole. The initial and intermediate catalytic reactors were each used in Example 1. Contained 1.1 m5 of catalyst. On the other hand, the last catalytic reactor has a specific area of 100 m2. / ; of alumina with a diameter of 4-1, impregnated with iron sulfate and having an iron content of 4 parts by weight; It contained 1.1 m3 of catalyst made of 6ranO spheres.

Each of the two catalytic converters of the supplementary purifier has a specific surface area of 100 m279 The catalyst bed consists of 25m5 alumina balls with a diameter of 4-6 cylinders, and an inlet and an inlet for the regeneration gas.

The converter inlet was separated from the corresponding outlet by a catalyst bed. installed in the converter The processing gas inlet was connected to the processing gas conduit through a gate valve. The latter is the last touch. Configure the inlet pipe of the supplementary purifier by connecting it to the outlet of the sulfur condenser belonging to the media reactor. On the other hand, the process gas outlet in the converter is connected to a supplementary purification system through a gate valve. It was connected to the process gas exhaust pipe that constitutes the outlet pipe of the plant. Regeneration gas outlet in the converter a sulfur condenser which cools the steam in series from said outlet through a gate valve; Connected to the inlet of the regeneration gas circuit including the lower and reheater, and the outlet of the reheater is partitioned. It was connected through a valve to the inlet for regeneration gas provided in the converter. converter inlet and outlet The sluice valves installed in the The sulfur gas is passed through one of the converters and the other converter is filled with sulfur from the reheater until it reaches the reheater. The hot regeneration gas flowed towards the condenser.

The catalytic desulfurization of the acidic force defined at the beginning of this example was carried out as follows.

Gas conduction of the first catalytic reactor at a flow rate of 1000 Nm3/h at a temperature of 40 °C. The acid gas introduced by the inlet pipe is absorbed by the small hole in said pipe at ambient temperature. It was mixed with air injected at a flow rate of 5 Nm3/h. This amount of air is 3 body purification corresponds to the theoretical amount of acid gas H2S required to oxidize sulfur. mole Ratio 02: H2S is brought to a temperature of 200°C by passing it through the acidic power of 017, and this temperature is The reactor was injected into the reactor at 100°C. said mixture and the catalyst contained in the first catalytic reactor; The contact time was 4 seconds. This corresponds to a VVH of 900h-1. first touch The gaseous effluent leaving the media reactor through its drain no longer contains free oxygen. At first, the temperature was 333"C. This effluent was a condensate belonging to the first catalytic reactor. It was cooled to 175°C in a vessel and the sulfur contained therein was separated. 175℃ temperature smell The gas coming out of the condenser with a H2S content of 5.6 vol. A small hole in the gas conduit of the medium reactor allows additional air at ambient temperature to be pumped up to 75 Nm3/ Added with h. This amount of new air is equivalent to the amount of H2S ions required for three-body purification of the gas. This corresponded to the theoretical amount required to oxidize corrugated iron. Molar ratio 02: H2S is 0.2 The resulting gas mixture of 7 is treated by passing it through a reheater belonging to the intermediate catalytic reactor. It was reheated to 200° C. and injected into the intermediate reactor at this temperature. This mixture and medium The contact time with the catalyst in the catalytic reactor was 4 seconds (VVH was 900 h-1 ). The gaseous effluent coming out of the intermediate catalytic reactor through its gas exhaust pipe is no longer It does not contain free oxygen, its temperature is 335°C, and its H2S content is 2.40% by volume. It was made.

This effluent is separated from the sulfur it contains in a condenser belonging to the intermediate catalytic reactor. Cool to 175°C.

The gas coming out of this condenser is surrounded by a small hole in the gas conduit of the last catalytic reactor. At ambient temperature, the molar ratio 02:H2S in the gaseous mixture thus obtained is 0. ．． Additional air was added to have a value of 5. This gaseous mixture enters the final catalytic reactor heated to a temperature of 200℃ by passing it through a reheater belonging to and then injected into the reactor. said force-like mixture and contained in the final catalytic reactor. The contact time with the alumina-based catalyst was 4 seconds (VVH was 9 00h-1). The gaseous effluent leaving the last catalytic reactor is no longer free oxygen. The temperature was 300°C. This effluent is separated from the sulfur it contains For this purpose, it was cooled to 135° C. in a condenser belonging to the last catalytic reactor.

As the only sulfur compound, H2S and 302 (0.77 volume coefficient) have a molar ratio of approximately 2=1. ' H2S and 068 volumetric purified o2) coming out of the condenser The effluent was transferred to the purification phase of the two converters of the supplementary purifier at a temperature of 135°C. I injected it into something. The other was in a regeneration phase. The contact time with Tonosu is 8 seconds ( VVH is 400h-1), H2S reacts with S02 in this catalyst and forms on alumina. It adhered to form sulfur. During this period, the converter, which is in the regeneration phase, is kept at a temperature of 300°C. In the reheater of the regeneration gas circuit, the nitrogen that comes out is purified and deposited on the catalyst. It was regenerated by removing the sulfur. Contains sulfur vapors coming out of the converter The nitrogen stream is cooled to 175°C by passing it through a sulfur condenser in the regeneration circuit to remove sulfur. Condensed. On the other hand, the sulfur-free nitrogen stream is passed through a reheater by a blower. 00°C and recycled towards the inlet of the converter in the regeneration phase. Pure Purified water exiting the reactor in the chemical phase and discharged by the drain of the supplementary purifier The gaseous effluent has a temperature of 140°C and a total content of H2S and S02 of 0092 vol. It only included.

The total conversion rate of H2S was 99. This converted H2S is completely in the form of sulfur. It was collected in

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Claims (1)

[Claims] 1-H2S and possibly a total amount of no more than 3 volumes of C82 and/or an acidic gas containing COS and a controlled amount of gas containing free oxygen; Titanium oxide is coated at a temperature of 100-600°C, preferably in the form of a mixture. The sulfur compounds are desulfurized by contact with a catalyst containing sulfur and sulfur. Depending on the case, the method is to recover it in the form of S02, and the catalyst may be other than titanium oxide. selected from the group of calcium, strontium, barium, and magnesium A method characterized by comprising a sulfate of an alkaline earth metal. 2- Characteristic that the alkaline earth metal sulfate in the catalyst is calcium sulfate The method according to claim 1. 3- In addition to titanium oxide and alkaline earth metal sulfates, there are up to 30 important catalysts selected from silica, alumina, clay, silicates, titanium sulfate, and ceramic fibers. The method according to claim 1 or 2, characterized in that the method comprises an isolated component. . 4- The weight proportion of titanium oxide in the catalyst is about 60-99% of the force-calcined catalyst, preferably or 80-99. How to put it on. 5- The weight ratio of alkaline earth metal sulfate in the catalyst is about 40-1 of the force-calcined catalyst. %, preferably 20-1%. The method described in 6- The specific area of the catalyst is 5-300 m2/g, preferably 1010-24O/g A method according to any one of claims 1 to 5, characterized in that: 7- The total pore volume of the catalyst determined by mercury infiltration method is 0.05-0.6Cm37g, preferably Claim 1-6, characterized in that it is preferably 0.1-0.4cm37g. The method described in any of the paragraphs. 8- Use one or more desulfurization zones and separate the gaseous reaction medium from each of these zones. The contact time with the catalyst inside the ax is 0.5-10 seconds, especially 1-6 seconds. 8. A method according to any one of claims 1 to 7, characterized in that: 9- Contacting a mixture of an acidic gas and a gas containing free oxygen with a catalyst is 1 Any of claims 1 to 8, characterized in that the process is carried out at a temperature of 80-500°C. The method described in 10 - Acid gas is at most 15 volumes of H2S and in some cases the total volume is at most 3 volume parts, preferably at most 1 volume part of C82 and/or COS. 10. A method according to any one of claims 1 to 9, characterized in that: In some cases, the total amount contains at most one volume of C82 and/or CO8. A method according to any one of claims 1 to 9, characterized in that: 12- Claims for treating acid gases containing possible amounts of H2S in the 5-volume class The method according to any one of the ranges 1 to 11, wherein the acid gas and free oxygen preferably in the form of a preformed mixture, in a molar ratio of 02: at a temperature of 180-500 °C in such an amount that the possible H2S has a value of 0.35-1.8. The gaseous reaction medium is brought into contact with the catalyst placed within the only catalytic zone that acts A method characterized in that the contact time between the body and the catalyst is 1-6 seconds. 13- The molar ratio 02° possible H2S value is 0.35-0.6, preferably 0 ．． 35-0.5 and the acid gas and free oxygen-containing gas in the catalyst region. When the initial temperature of 13. A method according to claim 12, characterized in that: 14- Requests for processing acid gases with a possible H2S content of more than about 5 volumes Any of the methods listed in Items 1 to 11 of the request range, - an initial catalyst optionally separated by one or more intermediate catalytic regions; a titanium oxide and an alkali metal sulfate, each containing a titanium oxide and an alkali metal sulfate region and a final catalytic region. passing the acid gas through a plurality of catalyst zones in series comprising; - inject a gas containing free oxygen into each said region, preferably in a mixture with an acidic gas; The ratio of oxygen entering each of the first and middle catalyst regions is in the 3-5 volume class of acid gas. About 0.7-1.2 of the possible H2S theoretically required to convert to sulfur 0.8-1 times, preferably about 0.8-1 times - in each catalyst area. Adjust the temperature of the gas to 180-350°C, preferably 200-250'C. - the contact time between the reactant gas and the catalyst in each zone is maintained at -6 seconds. and, - Treat the gaseous emissions coming from each initial and intermediate catalytic zone and reduce them by condensation. The sulfur contained in the waste is separated and the sulfur-free waste is sent to the inlet of the next area. To send to. - 02:possible H'2S molar ratio at the entrance of the last catalytic zone to 0.35-1 ．． Adjust to a value of 8 and, if necessary, treat the emissions in this area to ensure that it does not contain any separation of sulfur that may occur by condensation, provided that the number of intermediate catalytic regions is that at the inlet of the last catalytic region the acid gas is at most 5 volumes of possible H2S is something that includes A method characterized by: 15- Molar ratio o2 at the entrance of the last catalyst zone: possible H2S is 0.35 -0.5 cl+IEte, recovering possible 112s essentially in sulfur form 15. A method according to claim 14, characterized in that: 16- The effluent coming from a single catalyst zone or the last catalyst zone, if it contains After separating the sulfur that may be present, a supplementary purification process is carried out. 16. A method according to any of claims 12-15. 17- Requests for processing acid gases with a possible H2S content of more than about 5% by volume The method according to any one of claims 1 to 11, - an initial catalyst optionally separated by one or more intermediate catalytic regions; and a final catalytic region, each of said first and intermediate catalytic regions containing an acid. series comprising titanium chloride and an alkali metal sulfate of a predetermined type. passing said acid gas through multiple catalytic zones, provided that the catalyst used in the last catalytic zone; At least one-eighth, advantageously half, preferably all of the Catalyst made of a substrate containing a preponderance of alumina, preferably made entirely of alumina and at least selected from Fe, Co, Ni, Cu and Zn thereon. Compounds of metals, especially iron sulfate, were precipitated, and the substrate weighed 30-300 m37 g. It is advantageous to have a specific surface area of 50-120 m2/g, preferably 50-120 m2/g. The catalyst is preferably 0.5-10% by weight of the calcined catalyst. Preferably, it contains an amount of metal compound corresponding to 2-6% of the total amount of metal, a gas containing free oxygen in each said catalyst zone, preferably in a mixture with an acidic gas; The ratio of oxygen entering each of the first and middle catalytic regions is 3-5 volumes of acid gas. About 0.7-1.2 of the possible H2S theoretically required to convert to sulfur 0.8-1 times, preferably about 0.8-1 times - in each catalyst area. Adjust the temperature of the gas to 180-35°C, preferably 200-250'C. Lukoto - treats and condenses the gaseous effluents emerging from each initial and intermediate catalytic zone; The sulfur contained therein is separated by compression and the sulfur-removed effluent is passed to the next area. sending to the entrance of the area; By adjusting the molar ratio of - Obtaining an effluent containing sulfur in the gaseous effluent of the last catalyst zone; After separation, alumina-based standard A sulfur production reaction occurs between H2S and SO2 by contacting with the catalyst CLAUS. However, when the catalyst has sulfur attached to it, 2oo-4o. Regenerated by purification with free oxygen-free gas at a temperature of °C. Ru, A method characterized by: